Marrero, who finished 2-for-3 with four RBIs after replacing first baseman Brandon Belt in the fifth, followed Orlando Calixte's walk and Christian Arroyo's single off Reds right-hander Kevin Shackelford.

Marrero, who finished 2-for-3 with four RBIs after replacing first baseman Brandon Belt in the fifth, followed Orlando Calixte's walk and Christian Arroyo's single off Reds right-hander Kevin Shackelford.

The Reds jumped ahead with a pair of first-inning runs off San Francisco ace Madison Bumgarner.

Patrick Kivlehan's two-run, two-out single through the infield's left side opened the scoring and marred Bumgarner's lone inning of work. Bumgarner set up Kivlehan's hit by yielding Arismendy Alcantara's double and, with two outs, walking Adam Duvall and hitting Jesse Winker with a pitch to load the bases.

San Francisco halved the difference in its half of the first against Reds starter Rookie Davis as Joe Panik singled and scored on Hunter Pence's double. Facing Wandy Peralta, the Giants scored again in the fifth. Jimmy Rollins walked and came around on singles by Gordon Beckham and Marrero.

Replacing Davis was Reds prospect and roster candidate Sal Romano, who pitched two scoreless innings. Romano, trying to land a spot in the rotation or bullpen, allowed one hit with two walks and four strikeouts.

"I was very excited just to be out there, to be honest with you," Romano said. "It didn't really matter who was hitting but the fact that most of the Giants lineup was in there was a good test for me. Definitely a good start to spring. I felt like my fastball was there. I was able to elevate it when I wanted to and it was down for most of the time."

Cincinnati's Aristides Aquino smashed an RBI single off shortstop Calixte's glove in the seventh inning. That temporarily restored the Reds' two-run cushion and enabled them to survive the run that Wynton Bernard generated for the Giants in the eighth inning when he doubled and scored on a wild pitch.

WHAT'S NEXTReds: When the Reds return to Goodyear on Saturday, they will be the visiting team in the 3:05 p.m. ET game vs. the Indians, live on MLB.TV. It will mark the spring debut of regular players Joey Votto, Billy Hamilton and Eugenio Suarez while prospect and rotation candidate Amir Garrett is scheduled to start on the mound.

Giants: Besides facing a split-squad of Chicago Cubs, Matt Cain and Ty Blach will square off against each other, in a sense, as the pair of fifth-starter candidates make their Cactus League debuts in a 12:05 p.m. PT Scottsdale Stadium encounter, live on an exclusive webcast.